|Publication number||US4900133 A|
|Application number||US 07/263,149|
|Publication date||13 Feb 1990|
|Filing date||27 Oct 1988|
|Priority date||27 Oct 1988|
|Publication number||07263149, 263149, US 4900133 A, US 4900133A, US-A-4900133, US4900133 A, US4900133A|
|Inventors||Arthur L. Berman|
|Original Assignee||Kaiser Electronics|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (18), Non-Patent Citations (18), Referenced by (102), Classifications (16), Legal Events (4)|
|External Links: USPTO, USPTO Assignment, Espacenet|
1. Field of the Invention
The present invention relates generally to the field of display systems for use in aircraft, flight simulators, and the like, and more particularly to a system which combines a generated image with an image in an observer's line-of-sight by projecting the generated image onto a cholesteric liquid crystal combiner which reflects the projected image toward the observer together with images in the line-of-sight of the observer passing through the combiner.
2. Description of the Prior Art
In aircraft and other vehicles which require nearly continuous attention to both the outside environment and to instrumentation such as control, ordinance, etc., simultaneous viewing of both is desired. To accomplish this simultaneous viewing of both the outside environment and the instrumentation, heads-up displays (hereafter referred to as HUDs) are utilized. Such a typical prior art HUD system 8 is shown in FIG. 1. Typically, HUD systems consist of an instrumentation image source 10, such as a cathode ray tube (CRT), liquid crystal display (LCD), or similar display, an image combiner 12, and optics 16 for collimating the image. The combiner is usually angled relative to the line-of-sight plane of the observer so that the projected image in the image source plane is reflected into the line-of-sight plane of the observer. The observer views the outside environment through the combiner together with the projected instrumentation image, which appears as a virtual image focussed at infinity. Thus, the instrumentation image is, in effect, superimposed on the observer's view of the outside environment.
Presently, combiners fit into one of two categories semi-reflective combiners, and holographic combiners. Semi-reflective combiners are generally composed of a body of light-transmissive material, such as glass, having flat or selectively curved faces, one such face (usually that facing the observer) being provided with a semi-reflective thin-film coating of aluminum, silver, etc.
Light incident on a semi-reflective combiner from one direction is transmitted through it, and light incident on the combiner from the opposite direction is reflected by it. However, both absolute transmission and reflection is not possible. That is, to facilitate transmission of images from the outside environment through the combiner some degree of reflectivity of the projected images by the combiner must be sacrificed, and vice-versa. For this reason, semi-reflective mirrors as combiners have relatively poor transmissivity of images from the outside environment, and low contrast of the projected images as against the images from the outside environment. Further, aluminum coatings oxidize, silver coatings tarnish, etc., so that transmissivity and reflectivity tend to decrease with age of the combiner, especially at the shorter wavelengths. A typical semi-reflective mirror combiner will, at best, transmit approximately 75% of the light from the outside environment, while reflecting approximately 25% of the light comprising the projected image to the observer.
Holographic combiners generally consist of, in addition to an image source, diffraction optics in varying complexity. The diffraction optics serve as a combiner, and typically include a layer of photosensitive organic material such as a dichromated gelatin or photographic emulsion having a diffraction grating recorded thereon. This layer is sandwiched between two layers of glass which provide structural support and protect it from physical damage. Under the principal of Bragg diffraction, the diffraction grating will diffract and reflect light in a selected bandwidth, and transmit light outside the selected bandwidth.
In operation, the holographic combiner is placed in the line-of-sight plane of an observer. All images from the outside environment in the line-of-sight plane of the observer, except for those at the diffraction/reflection wavelength, pass through the combiner. Those images at the diffraction/reflection wavelength are reflected away from the observer. A projected image at the diffraction/reflection wavelength of the diffraction grating, incident upon the combiner, is reflected in the line-of-sight plane of the observer so as to appear superimposed on the images from the outside environment.
The holographic combiner works on the principal of exposed recording media, namely utilizing the photosensitive layer. Recorded on the media is a matrix of exposed images of dots, or a grid of lines. Light incident upon the recorded images (i.e., the matrix or grid) is reflected by the holographic combiner. The light striking the holographic combiner between the recorded images passes through it undiffracted and unreflected. This implies that holographic combiners have less than absolute reflectivity. Further, light from the outside environment is filtered by the holographic combiner such as to reduce its transmission, due to the fact that the photosensitive layer is not perfectly transmissive. In effect, typical holographic combiners transmit between 70% and 80% efficiency, while reflecting projected images at between 70% and 80% efficiency.
Low transmissivity and reflectivity of the combiner is undesirable, especially in low visibility operating conditions such as at night or in inclement weather. Further, in flight simulator applications and the like it is crucial to keep the required brightness of images generated in the trainee's line-of-sight plane to a minimum in order to minimize the cost of operation and maximize the life-span of simulator image projection equipment.
Thus, there is a present need in the art for a combiner with higher transmissivity of images from the outside environment, simulator images, etc., and further with higher reflectivity of projected images such as instrumentation, etc., while maintaining the weight, complexity and cost of the optics to a minimum.
The present invention is directed to an HUD combiner that utilizes the properties of cholesteric liquid crystals to superimpose projected images upon images in the observer's line-of-sight. The combiner of the present invention thereby provides a high transmissivity of images in the line-of-sight plane of the observer, together with a high reflectivity of images projected upon it, not heretofore obtained.
According to a preferred embodiment of the present invention, a combiner for an HUD system is formed with two flat cholesteric liquid crystal elements, each reflective to light within a certain bandwidth having opposite rotary sense. A CRT and collimating optics are positioned to project images, representing instrument readings, for example, upon the combiner in such a way as to be reflected into the line-of-sight plane of the observer. The combiner is placed in the line-of-sight plane of the observer so that images from the CRT, reflected into the line-of-sight of the observer, appear superimposed upon images from the outside environment, simulator, etc.
The combiner for an HUD system according to the present invention provides higher transmissivity of images from the outside environment, and higher reflectivity of projected images, such as instrumentation, than heretofore provided by the prior art. Further, weight, complexity of the components, and cost are reduced over the prior art.
FIG. 1 illustrates a prior art HUD system with combiner.
FIG. 2 illustrates a HUD system according to one embodiment of the present invention utilizing dual cholesteric liquid crystal elements.
FIG. 3(a) illustrate the transmission characteristics of a cholesteric liquid crystal element reflective to RHCP green light.
FIG. 3(b) is a graph of transmission and polarization efficiency of a cholesteric liquid crystal element.
FIG. 4 illustrates an HUD system according to one embodiment of the present invention utilizing dual cholesteric liquid crystal elements and a half-wave-length filter.
FIG. 5 illustrates an HUD system according to another embodiment of the present invention utilizing a single cholesteric liquid crystal element and circular polarizing filter.
FIG. 6 is a graph illustrating the angular dependence of the wavelength of maximum reflection.
FIGS. 7(a) and 7(b) illustrate the biasing of the reflection angle from the cholesteric liquid crystal element through the use of surface tilt, untilted and tilted cases, respectively.
With reference to FIG. 2, a preferred embodiment of an HUD system 18, utilizing cholesteric liquid crystal combiner 20 according to the present invention, is shown. As illustrated, HUD system 18 includes combiner 20, together with an image source 22, and collimating optics 24.
Combiner 20, in the preferred embodiment, comprises first and second cholesteric elements 26 and 28, respectively. First cholesteric liquid crystal element 26 is tuned to reflect right hand circular polarized (RHCP) light in a bandwidth, B, around 540 Nm (i..e, green light), and second cholesteric liquid crystal element 28 is tuned to reflect left hand circular polarized (LHCP) light in that same bandwidth, B. That is, first cholesteric liquid crystal element 26 is reflective to images that are RHCP and in the bandwidth B and transmissive to all other images, and second cholesteric liquid crystal element 28 is reflective to images that are LHCP and in the bandwidth B. First and second cholesteric elements 26, 28 are, in one embodiment, separate elements, and positioned roughly parallel to one another. However, other embodiments of the present invention will have first and second cholesteric elements 26, 28 joined as one element, or oriented a parallel to one another, dependent on the intended application.
Image source 22 may be a cathode ray tube (CRT), liquid crystal display (LCD), or other type of display. In general, image source 22 is capable of generating images of instrumentation, for example aircraft altitude, bearing, fuel reserve level, gun-sights, etc. Image source 22 is preferably a green CRT having a phosphor coating, P43 or P53 for example, with a narrow bandwith of transmission centered around 540 Nm. The brightness of image source 22 must be sufficient to be perceived by an observer, symbolized by an eye labelled O, after reflection, but due to the high reflectivity of a combiner constructed according to the present invention, the brightness of image source 22 may be kept to a minimum.
Collimating optics 24 may consist of various lenses, etc., and will be arranged as a function of the relative positions of combiner 20, image source 22, and observer O. The effect of collimation is to focus the images from image source 22 at some distance in the line-of-sight plane of observer O. For aircraft HUD applications, a collimated focus between 40 feet and infinity is preferred.
HUD system 18 is positioned in an aircraft cockpit, or similar location, such that combiner 20 lies between the outside environment and observer O, in the plane of the observer's line-of-sight. Collimating optics 24 are positioned between combiner 20 and image source 22. Image source 22 is positioned such that images generated thereby are incident on, and reflected by, combiner 20 into the line-of-sight plane of observer O.
To better enable a comprehensive understanding of the functioning of the present invention, a brief description of cholesteric liquid crystal elements may be beneficial.
Cholesteric liquid crystals of the type employed in the present invention exhibit a number of unique properties with regard to light incident upon them. Specific to the present invention are several properties of such liquid crystals, explained with reference to FIGS. 3(a) and 3(b). A cholesteric liquid crystal element (or cholesteric element) is substantially transparent to all wavelengths of electromagnetic radiation, specifically visible light, except that within a narrow bandwidth, B, around a selected primary wavelength, for example 540 Nm (i.e., green), as shown in FIG. 3(a). Within bandwidth B, light of one rotary sense (LHCP or RHCP) incident upon the cholesteric element from either direction is reflected by the cholesteric element. By convention, a cholesteric element which is reflective to right-hand circular polarized light is said to be a right-hand circular polarized (or right-handed) cholesteric element. Conversely, a cholesteric liquid crystal element which is reflective to left-hand circular polarized light is said to be a left-hand circular polarized (or left-handed) cholesteric element. See Adams, et al., CHOLESTERIC FILMS AS OPTICAL FILTERS, "Journal of Applied Physics," Vol. 42, no. 10 (1971).
Further, light reflected by the cholesteric element maintains original rotary sense (i.e., does not change handedness). For example, RHCP light reflected by a cholesteric element is reflected as RHCP light. This is counter to the general case of other surfaces, where reflection is accompanied by a change of rotary sense (i.e., RHCP light incident upon a reflective surface is reflected as LHCP light).
The same is true with respect to transmission of light through a cholesteric element. Light of a first rotary sense passing through a cholesteric element maintains that first rotary sense. For example, RHCP light passing through a left-handed cholesteric element remains RHCP.
As FIG. 3(b) illustrates, cholesteric elements have very high transmissivity and reflectance around the primary wavelength. A cholesteric element is capable of achieving transmission of 90% for all light except that of one rotary sense within the bandwidth, B, around the primary wavelength, for which light the element is capable of 90% reflection. In HUD applications, this provides the observer with acute visibility of images of the outside environment, transmitted through the cholesteric element, combined with high-contrast projected symbology, reflected off the element.
Operation of HUD system 18 according to a preferred embodiment of the present invention will now be described with reference to FIG. 2. Observer O is positioned to receive images from the outside environment through combiner 20. Green light emitting from image source 22, of equal parts LHCP and RHCP, is collimated by collimating optics 24, and caused to be incident upon first cholesteric element 26. The RHCP portion of light incident upon first cholesteric element 26 is reflected into the line-of-sight plane of observer O, while the LHCP portion of the light is transmitted unattenuated by first cholesteric element 26 and caused to be incident upon second cholesteric element 28. The LHCP light incident upon second cholesteric element 28 is reflected into the line-of-sight plane of observer O by second cholesteric element 28, passing unattenuated through first cholesteric element 26.
All images from the outside environment in the line-of-sight plane of observer O not within bandwidth B are transmitted through first and second cholesteric elements 26, 28 to observer O. Those images within bandwidth B which are LHCP are reflected away from observer O by second cholesteric element 28, and those which are RHCP are reflected away from observer O by first cholesteric element 26.
Because cholesteric elements exhibit high transmissivity, better viewing of images of the outside environment is provided. Further, since cholesteric elements are reflective to light within a selected bandwidth incident upon them from either direction, images from the outside environment within the reflective bandwidth are reflected away from observer O. Thus, the projected images within the bandwidth B have a higher contrast as against images from the outside environment. Consequently, image source 22 need be of a lower power than that used in the prior art. This lowers the cost and complexity of HUD system 18.
With reference to FIG. 4, another embodiment of the present invention is shown. In this embodiment, HUD system 18' consists of an image source 32, similar to that described above, collimating optics 34, again as described above, and combiner 20', comprising first and second cholesteric elements 36 and 38 respectively. Between first and second cholesteric elements 36, 38 is positioned half wavelength filter 40. First and second cholesteric elements 36, 38 are formed to be RHCP, both having a bandwidth, B, of reflection centered around 540 Nm (green light). First and second cholesteric elements 36, 38, and halffl-wavelength filter 40 are positioned in the line-of-sight plane of observer O, and further in the path of incidence of image source 32.
In operation, green light emitting from image source 32, of equal parts LHCP and RHCP, is collimated by collimating optics 34 and caused to be incident upon first cholesteric element 36. RHCP light incident upon first cholesteric element 36 is reflected into the line-of-sight plane of observer O, while LHCP light is transmitted unattenuated by first cholesteric element 36 and caused to be incident upon half-wavelength filter 40. Light passing through half-wavelength filter 40 is caused to reverse its rotary sense (i.e., LHCP light is reversed to RHCP light). Light passing through half-wavelength filter 40 is caused to be incident upon second cholesteric element 38, which reflects the now RHCP light into the line-of-sight plane of observer O. Intermediate to reaching observer O, the light reflected by second cholesteric element 38 passes once more through halfwavelength filter 40, undergoing a second reversal of rotary sense (i.e., RHCP to LHCP), so as to pass unattenuated through first cholesteric element 36 to observer O.
Since the optical properties of a cholesteric element are directly dependent on the temperature of the cholesteric liquid crystal material, the embodiment as detailed above (FIG. 4) uses two identical cholesteric elements to minimize the effects of temperature shifts on the optical performance of the combiner. Properties such as the dependence of the reflected wavelength on the angle of incidence (further discussed below) can also be better controlled when identical cholesteric elements are used.
As detailed in FIG. 5, another embodiment of an HUD system 18'' according to the present invention has a combiner 20'' comprised of a single cholesteric element 48, tuned to reflect green RHCP light, and located in the line-of-sight plane of observer O. HUD system 18'' further comprises image source 42, collimating optics 44, and circular polarizing filter 46. This embodiment is most commonly used in situations where image source 42 is provided with a polarizing filter to reduce reflection from external light, such as sunlight.
In operation, light emitting from image source 42, which is RHCP is collimated by collimating optics 44, and transmitted to cholesteric element 48 by circular polarizing filter 46. Light which is LHCP, on the other hand, is substantially entirely filtered out by circular polarizing filter 46. Thus, images projected upon cholesteric element 48 by image source 42 are predominantly RHCP, and consequently reflected by cholesteric element 48 so as to be combined with images passing through cholesteric element 48 from the outside environment.
In general to those skilled in the art to which this invention relates, many changes in construction and widely differing embodiments and applications of the present invention will suggest themselves without departing from its spirit and scope. For example, the composition of the cholesteric combiner may be such that it has a bandwidth of maximum reflection centered at a wavelength other than 540 Nm. Likewise, the bandwidth of maximum reflection around the primary wavelength may be varied as a function of the cholesteric liquid crystal's composition.
Further, the physical arrangement of components of the invention may be varied with specific results. For example, relying on another property of cholesteric elements, as demonstrated in FIG. 6, that the wavelength of maximum reflection is angular sensitive (i.e., as the angle of incidence increases, the wavelength of maximum reflection is shifted toward the shorter wavelengths) the wavelength of maximum reflection of the cholesteric liquid crystal element for normally incident light may be increased to compensate for the shift toward the shorter wavelengths of reflection for non-normally incident light.
Another property of cholesteric elements, demonstrated in FIGS. 7(a) and 7(b), is that the separation between the angle of incidence i and angle of reflection r is a function of the orientation, or tilt, of the helical axis of the cholesteric layer. As the helical axis of the cholesteric layer. As the helical axis is tilted away from normal to the surface of the cholesteric liquid crystal element the separation becomes smaller. Thus, positioning of the reflected image in the line-of-sight of the observer may be controlled by the composition of the element (as opposed to positioning of the image source).
Thus, the disclosures and descriptions herein are purely illustrative, and are not intended to be in any sense limiting.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3679290 *||6 Jan 1971||25 Jul 1972||Xerox Corp||Liquid crystal optical filter system|
|US3697154 *||12 May 1971||10 Oct 1972||Us Navy||Optical viewing system|
|US3711181 *||5 Mar 1971||16 Jan 1973||Xerox Corp||Optical notch filter|
|US3915548 *||29 Nov 1974||28 Oct 1975||Hughes Aircraft Co||Holographic lens and liquid crystal image source for head-up display|
|US3957348 *||26 Mar 1975||18 May 1976||Xerox Corporation||Method for altering elliptically polarized light|
|US4026641 *||30 Dec 1975||31 May 1977||The United States Of America As Represented By The Secretary Of The Army||Toric reflector display|
|US4269475 *||3 Oct 1979||26 May 1981||Elliott Brothers (London) Limited||Head-up displays|
|US4398799 *||24 Feb 1981||16 Aug 1983||Pilkington P.E. Limited||Head-up displays|
|US4407564 *||21 Jan 1981||4 Oct 1983||Elliott Brothers (London) Limited||Head-up displays|
|US4447128 *||3 Dec 1982||8 May 1984||Hughes Aircraft Company||Diffraction head up display solar radiation filter|
|US4582394 *||15 Jun 1983||15 Apr 1986||Pilkington P.E. Limited||Display apparatus|
|US4600271 *||29 Feb 1984||15 Jul 1986||Thomson Csf||Head-up display|
|US4611877 *||9 Aug 1985||16 Sep 1986||Gec Avionics Limited||Optical projectors for head up displays|
|US4613200 *||9 Jul 1984||23 Sep 1986||Ford Motor Company||Heads-up display system with holographic dispersion correcting|
|EP0154953A2 *||9 Mar 1985||18 Sep 1985||Matsushita Electric Industrial Co., Ltd.||Optical filter and the method of preparing the same|
|GB1321303A *||Title not available|
|GB1529227A *||Title not available|
|GB2149140A *||Title not available|
|1||"Holographic `Mirror` Helps Fighter Pilots to See", Engineering Materials Design, vol. 31, No. 4, Apr. 1987; p. 15.|
|2||D. M. Makow, "Peak Reflectance & Color Gamut of Superimposed Left- and Right-Handed Cholesteric Liquid Crystals", Applied Optics, vol. 19, No. 8, 4/15/1980.|
|3||*||D. M. Makow, Peak Reflectance & Color Gamut of Superimposed Left and Right Handed Cholesteric Liquid Crystals , Applied Optics, vol. 19, No. 8, 4/15/1980.|
|4||*||Holographic Mirror Helps Fighter Pilots to See , Engineering Materials Design, vol. 31, No. 4, Apr. 1987; p. 15.|
|5||IBM Technical Disclosure Bulletin, "Light Beam Combiner", vol. 15, No. 4, Sep. 1972.|
|6||*||IBM Technical Disclosure Bulletin, Light Beam Combiner , vol. 15, No. 4, Sep. 1972.|
|7||J. Adams et al., "Cholesteric Films as Optical Filters", Journal of Applied Physics, vol. 42, No. 10, Sep. 1971.|
|8||*||J. Adams et al., Cholesteric Films as Optical Filters , Journal of Applied Physics, vol. 42, No. 10, Sep. 1971.|
|9||Jenkins & White, "Fundamentals of Optics", p. 567, McGraw-Hill, 1976.|
|10||*||Jenkins & White, Fundamentals of Optics , p. 567, McGraw Hill, 1976.|
|11||Kahn, "Cholesteric Liquid Crystals for Optical Application", Appl. Phys. Letters, vol. 18, No. 6, Mar. 15, 1971, pp. 231-233.|
|12||*||Kahn, Cholesteric Liquid Crystals for Optical Application , Appl. Phys. Letters, vol. 18, No. 6, Mar. 15, 1971, pp. 231 233.|
|13||Melamed et al., "Selected Optical Properties of Mixtures of Cholesteric Liquid Crystal", Applied Optics, vol. 10, No. 5, May 1971.|
|14||*||Melamed et al., Selected Optical Properties of Mixtures of Cholesteric Liquid Crystal , Applied Optics, vol. 10, No. 5, May 1971.|
|15||P. G. deGennes, "The Physics of Liquid Crystals", chapter 1 titled Anisotropic Fluids: Main Types & Properties, Clanedon Press, 1974.|
|16||*||P. G. deGennes, The Physics of Liquid Crystals , chapter 1 titled Anisotropic Fluids: Main Types & Properties, Clanedon Press, 1974.|
|17||W. A. Shurcliff, "Polarized Light", chapter titled Retarders and Circular Polarizers, Harvard University Press, 1962.|
|18||*||W. A. Shurcliff, Polarized Light , chapter titled Retarders and Circular Polarizers, Harvard University Press, 1962.|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US5015188 *||26 Dec 1989||14 May 1991||The United States Of America As Represented By The Secretary Of The Air Force||Three dimensional tactical element situation (3DTES) display|
|US5050966 *||6 Jul 1988||24 Sep 1991||Kaiser Aerospace & Electronics Corporation||Optical combiner collimating apparatus|
|US5235443 *||24 Feb 1992||10 Aug 1993||Hoffmann-La Roche Inc.||Polarizer device|
|US5293513 *||8 Apr 1991||8 Mar 1994||Mitsubishi Denki Kabushiki Kaisha||Switching system for automotive vehicle including a reflector positioned below a sight line of a driver|
|US5295009 *||7 May 1993||15 Mar 1994||Hoffmann-La Roche||Polarizer device|
|US5343313 *||2 Sep 1993||30 Aug 1994||James L. Fergason||Eye protection system with heads up display|
|US5408346 *||20 Oct 1993||18 Apr 1995||Kaiser Electro-Optics, Inc.||Optical collimating device employing cholesteric liquid crystal and a non-transmissive reflector|
|US5418631 *||14 May 1993||23 May 1995||Kaiser Optical Systems, Inc.||Edge-lit holographic diffusers for flat-panel displays|
|US5421589 *||7 Sep 1993||6 Jun 1995||The Walt Disney Company||Method and apparatus for displaying an alpha channel virtual image|
|US5526022||6 Jan 1993||11 Jun 1996||Virtual I/O, Inc.||Sourceless orientation sensor|
|US5541745 *||25 Jan 1994||30 Jul 1996||Fergason; James L.||Illumination system for a display using cholesteric liquid crystal reflectors|
|US5552935 *||21 May 1989||3 Sep 1996||Robert Bosch Gmbh||Head-up display device for motor vehicles|
|US5566025 *||18 May 1995||15 Oct 1996||Robert Bosch Gmbh||Head-up display device for motor vehicles|
|US5585967 *||7 Sep 1993||17 Dec 1996||The Walt Disney Company||Three dimensional virtual image system|
|US5619377 *||8 May 1995||8 Apr 1997||Virtual I/O, Inc.||Optically corrected helmet mounted display|
|US5642227 *||6 Jun 1995||24 Jun 1997||Virtual I/O, Inc.||Optical correction for virtual reality and heads up displays|
|US5644323 *||21 Dec 1994||1 Jul 1997||Siliscape, Inc.||Miniature synthesized virtual image electronic display|
|US5673151 *||6 Jun 1995||30 Sep 1997||Virtual I/O||Image correction in virtual reality and heads up displays|
|US5694230 *||7 Jun 1995||2 Dec 1997||Digital Optics Corp.||Diffractive optical elements as combiners|
|US5767820 *||9 May 1995||16 Jun 1998||Virtual Research Systems||Head-mounted visual display apparatus|
|US5771124 *||2 Jul 1996||23 Jun 1998||Siliscape||Compact display system with two stage magnification and immersed beam splitter|
|US5790209 *||20 Feb 1997||4 Aug 1998||Northrop Grumman Corporation||Canopy transmittal reflectance control and information display|
|US5793450 *||10 Nov 1994||11 Aug 1998||Grumman Aerospace Corporation||Canopy transmittal reflectance control and information display|
|US5828495 *||31 Jul 1997||27 Oct 1998||Eastman Kodak Company||Lenticular image displays with extended depth|
|US5838498 *||31 Dec 1996||17 Nov 1998||Siliscape, Inc.||Miniature synthesized virtual image electronic display|
|US5859714 *||8 Jan 1997||12 Jan 1999||Asahi Glass Company, Ltd.||Head-up display, a combiner used for the head-up display and a method of designing the head-up display|
|US5864326 *||7 Feb 1994||26 Jan 1999||I-O Display Systems Llc||Depixelated visual display|
|US5870068 *||1 Apr 1997||9 Feb 1999||Siliscape, Inc.||Twice folded compound magnified virtual image electronic display|
|US5903395 *||31 Aug 1994||11 May 1999||I-O Display Systems Llc||Personal visual display system|
|US5903396 *||17 Oct 1997||11 May 1999||I/O Display Systems, Llc||Intensified visual display|
|US5905478 *||1 Apr 1997||18 May 1999||Siliscape, Inc.||Twice folded compound magnified virtual image electronic display|
|US5949583 *||7 Jun 1995||7 Sep 1999||I-O Display Systems Llc||Head-mounted display with image generator, fold mirror and mirror for transmission to the eye position of the user|
|US5959781 *||26 Jan 1999||28 Sep 1999||Inviso||Optical method employing total internal reflection|
|US5973845 *||29 Oct 1998||26 Oct 1999||Hildebrand; Alfred P.||Miniature synthesized virtual image electronic display|
|US5991085||12 Jul 1996||23 Nov 1999||I-O Display Systems Llc||Head-mounted personal visual display apparatus with image generator and holder|
|US5991087 *||6 Jun 1995||23 Nov 1999||I-O Display System Llc||Non-orthogonal plate in a virtual reality or heads up display|
|US6005714 *||2 Dec 1997||21 Dec 1999||Digital Optics Corporation||Two layer optical elements|
|US6055110 *||11 Aug 1999||25 Apr 2000||Inviso, Inc.||Compact display system controlled by eye position sensor system|
|US6097543 *||31 Aug 1994||1 Aug 2000||I-O Display Systems Llc||Personal visual display|
|US6101431 *||21 Aug 1998||8 Aug 2000||Kawasaki Jukogyo Kabushiki Kaisha||Flight system and system for forming virtual images for aircraft|
|US6160666 *||23 Mar 1998||12 Dec 2000||I-O Display Systems Llc||Personal visual display system|
|US6307604 *||2 Feb 1995||23 Oct 2001||U.S. Philips Corporation||Light source having a luminescent layer|
|US6404557||8 Dec 2000||11 Jun 2002||Inviso, Inc.||Display illumination system|
|US6433935||10 Sep 1999||13 Aug 2002||Three-Five Systems, Inc.||Display illumination system|
|US6456438||12 Aug 1999||24 Sep 2002||Honeywell Inc.||Variable immersion vignetting display|
|US6603443||29 Oct 1998||5 Aug 2003||Three-Five Systems, Inc.||Compact display system controlled by eye position sensory system|
|US6612840 *||28 Apr 2000||2 Sep 2003||L-3 Communications Corporation||Head-up display simulator system|
|US6639569||14 Dec 2000||28 Oct 2003||Ford Global Technologies, Llc||Integrated heads-up display and cluster projection panel assembly for motor vehicles|
|US6844980 *||23 Apr 2002||18 Jan 2005||Reveo, Inc.||Image display system and electrically actuatable image combiner therefor|
|US6952312||31 Dec 2002||4 Oct 2005||3M Innovative Properties Company||Head-up display with polarized light source and wide-angle p-polarization reflective polarizer|
|US7095562||4 Aug 2005||22 Aug 2006||Rockwell Collins, Inc.||Advanced compact head up display|
|US7123418||29 Jul 2005||17 Oct 2006||3M Innovative Properties Company||Head-up display with narrow band reflective polarizer|
|US7203005 *||22 May 2003||10 Apr 2007||Chelix Technologies, Inc.||Real image configuration for a high efficiency heads-up display (HUD) using a polarizing mirror and a polarization preserving screen|
|US7397606||4 Aug 2005||8 Jul 2008||Rockwell Collins, Inc.||Meniscus head up display combiner|
|US7513668||4 Aug 2005||7 Apr 2009||Rockwell Collins, Inc.||Illumination system for a head up display|
|US7619825||27 Sep 2004||17 Nov 2009||Rockwell Collins, Inc.||Compact head up display with wide viewing angle|
|US8593521||30 Nov 2012||26 Nov 2013||Magna Electronics Inc.||Imaging system for vehicle|
|US8599001||19 Nov 2012||3 Dec 2013||Magna Electronics Inc.||Vehicular vision system|
|US8629768||18 Jun 2012||14 Jan 2014||Donnelly Corporation||Vehicle vision system|
|US8636393||6 May 2013||28 Jan 2014||Magna Electronics Inc.||Driver assistance system for vehicle|
|US8637801||8 Jul 2013||28 Jan 2014||Magna Electronics Inc.||Driver assistance system for a vehicle|
|US8643724||13 Mar 2013||4 Feb 2014||Magna Electronics Inc.||Multi-camera vision system for a vehicle|
|US8665079||15 Oct 2012||4 Mar 2014||Magna Electronics Inc.||Vision system for vehicle|
|US8818042||18 Nov 2013||26 Aug 2014||Magna Electronics Inc.||Driver assistance system for vehicle|
|US8842176||15 Jan 2010||23 Sep 2014||Donnelly Corporation||Automatic vehicle exterior light control|
|US8886401||4 Nov 2013||11 Nov 2014||Donnelly Corporation||Driver assistance system for a vehicle|
|US8917169||2 Dec 2013||23 Dec 2014||Magna Electronics Inc.||Vehicular vision system|
|US8977008||8 Jul 2013||10 Mar 2015||Donnelly Corporation||Driver assistance system for vehicle|
|US8993951||16 Jul 2013||31 Mar 2015||Magna Electronics Inc.||Driver assistance system for a vehicle|
|US9008369||25 Aug 2014||14 Apr 2015||Magna Electronics Inc.||Vision system for vehicle|
|US9014904||23 Sep 2013||21 Apr 2015||Magna Electronics Inc.||Driver assistance system for vehicle|
|US9122052 *||21 Aug 2013||1 Sep 2015||Commissariat à l'énergie atomique et aux énergies alternatives||Compact head-up display|
|US9131120||15 May 2013||8 Sep 2015||Magna Electronics Inc.||Multi-camera vision system for a vehicle|
|US9171217||3 Mar 2014||27 Oct 2015||Magna Electronics Inc.||Vision system for vehicle|
|US9191574||13 Mar 2013||17 Nov 2015||Magna Electronics Inc.||Vehicular vision system|
|US9191634||3 Apr 2015||17 Nov 2015||Magna Electronics Inc.||Vision system for vehicle|
|US9193303||20 Apr 2015||24 Nov 2015||Magna Electronics Inc.||Driver assistance system for vehicle|
|US9329388||6 Jan 2012||3 May 2016||Google Inc.||Heads-up display for a large transparent substrate|
|US9376060||16 Nov 2015||28 Jun 2016||Magna Electronics Inc.||Driver assist system for vehicle|
|US9395542||7 Nov 2012||19 Jul 2016||Elbit Systems Of America, Llc||Projecting synthetic imagery and scenic imagery using an optical component comprising a diffractive optical element pattern|
|US9428192||16 Nov 2015||30 Aug 2016||Magna Electronics Inc.||Vision system for vehicle|
|US9436880||13 Jan 2014||6 Sep 2016||Magna Electronics Inc.||Vehicle vision system|
|US9440535||27 Jan 2014||13 Sep 2016||Magna Electronics Inc.||Vision system for vehicle|
|US9555803||16 May 2016||31 Jan 2017||Magna Electronics Inc.||Driver assistance system for vehicle|
|US20020171940 *||23 Apr 2002||21 Nov 2002||Zhan He||Image display system and electrically actuatable image combiner therefor|
|US20040008412 *||22 May 2003||15 Jan 2004||Yingqlu Jiang||Real image configuration for a high efficiency heads-up display (HUD) using a polarizing mirror and a polarization preserving screen|
|US20040135742 *||31 Dec 2002||15 Jul 2004||Weber Michael F.||Head-up display with polarized light source and wide-angle p-polarization reflective polarizer|
|US20050140573 *||1 Dec 2003||30 Jun 2005||Andrew Riser||Image display system and method for head-supported viewing system|
|US20050270655 *||29 Jul 2005||8 Dec 2005||3M Innovative Properties Company||Head-up display with narrow band reflective polarizer|
|US20070279755 *||1 Jun 2006||6 Dec 2007||3M Innovative Properties Company||Head-Up Display System|
|US20100066925 *||15 Sep 2009||18 Mar 2010||Kabushiki Kaisha Toshiba||Head Up Display|
|US20140055865 *||21 Aug 2013||27 Feb 2014||Commissariat A L'energie Atomique Et Aux Energies Alternatives||Compact head-up display|
|CN104169779A *||7 Nov 2012||26 Nov 2014||美国埃尔比特系统有限责任公司||System and method for projecting synthetic imagery and scenic imagery using an optical component comprising a diffractive optical element pattern|
|CN104169779B *||7 Nov 2012||14 Dec 2016||美国埃尔比特系统有限责任公司||使用包括衍射光学元件图案的光学部件对合成像与场景像进行投影的系统及方法|
|DE102013206505A1 *||12 Apr 2013||16 Oct 2014||Bayerische Motoren Werke Aktiengesellschaft||Lichtdurchlässige Scheibe zum Anzeigen eines Bildes eines Head-Up Displays für polarisierte Sonnenbrillen|
|EP2776885A4 *||7 Nov 2012||15 Jul 2015||Elbit Systems America Llc||System and method for projecting synthetic imagery and scenic imagery using an optical component comprising a diffractive optical element pattern|
|WO1996038319A2||22 May 1996||5 Dec 1996||Donnelly Corporation||Rearview vision system for vehicle including panoramic view|
|WO2001016640A2 *||11 Aug 2000||8 Mar 2001||Honeywell, Inc.||Variable immersion vignetting display|
|WO2001016640A3 *||11 Aug 2000||20 Sep 2001||Allied Signal Inc||Variable immersion vignetting display|
|WO2001084522A2 *||20 Apr 2001||8 Nov 2001||L-3 Communications Corporation||Head-up display simulator system|
|WO2001084522A3 *||20 Apr 2001||7 Mar 2002||L 3 Comm Corp||Head-up display simulator system|
|WO2002086591A1 *||23 Apr 2002||31 Oct 2002||Reveo, Inc.||Image display system and electrically actuatable image combiner therefor|
|U.S. Classification||349/11, 359/630, 349/194, 349/176, 359/13|
|International Classification||G02B5/30, G02B27/01, G02B27/00|
|Cooperative Classification||G02B5/3016, G02B2027/0118, G02B5/30, G02B27/0101, G02B27/01|
|European Classification||G02B5/30L, G02B27/01A, G02B27/01|
|27 Oct 1988||AS||Assignment|
Owner name: KAISER ELECTRONICS, 2701 ORCHARD PARKWAY, SAN JOSE
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:BERMAN, ARTHUR L.;REEL/FRAME:004970/0666
Effective date: 19881024
Owner name: KAISER ELECTRONICS, CALIFORNIA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:BERMAN, ARTHUR L.;REEL/FRAME:004970/0666
Effective date: 19881024
|8 Mar 1993||FPAY||Fee payment|
Year of fee payment: 4
|20 Jun 1997||FPAY||Fee payment|
Year of fee payment: 8
|29 Jun 2001||FPAY||Fee payment|
Year of fee payment: 12